Adaptive modeling and high quality spectral estimation for speech enhancement

In this work an adaptive modeling and spectral estimation scheme based on a dual Discrete Kalman Filtering (DKF) is proposed for speech enhancement. Both speech and noise signals are modeled by an autoregressive structure which provides an underlying time frame dependency and improves time-frequency resolution. The model parameters are arranged to obtain a combined state-space model and are also used to calculate instantaneous power spectral density estimates. The speech enhancement is performed by a dual discrete Kalman filter that simultaneously gives estimates for the models and the signals. This approach is particularly useful as a pre-processing module for parametric based speech recognition systems that rely on spectral time dependent models. The system performance has been evaluated by a set of human listeners and by spectral distances. In both cases the use of this pre-processing module has led to improved results.

Adaptive filtering for high quality HMM based speech synthesis

In this work an adaptive filtering scheme based on a dual Discrete Kalman Filtering (DKF) is proposed for Hidden Markov Model (HMM) based speech synthesis quality enhancement. The objective is to improve signal smoothness across HMMs and their related states and to reduce artifacts due to acoustic model's limitations. Both speech and artifacts are modelled by an autoregressive structure which provides an underlying time frame dependency and improves time-frequency resolution. Themodel parameters are arranged to obtain a combined state-space model and are also used to calculate instantaneous power spectral density estimates. The quality enhancement is performed by a dual discrete Kalman filter that simultaneously gives estimates for the models and the signals. The system's performance has been evaluated using mean opinion score tests and the proposed technique has led to improved results.

Microbiological quality of drinking rainwater in the inland region of Pajeú, Pernambuco, Northeast Brazil

Despite all efforts to store and reduce its consumption, water is becoming less inexhaustible and its quality is falling faster. Considering that water is essential to animal life, it is necessary to adopt measures to ensure its sanitary conditions in order to be fit for consumption. The aim of this study was to analyze the microbiological quality of drinking rainwater used by rural communities of Tuparetama, a small town located in Northeast Brazil. The study covered seven rural communities, totaling 66 households. In each household two samples were collected, one from a tank and the other from a clay pot located inside the home, resulting in 132 samples (tank plus clay pot). Approximately 90% of samples were below the standard recommended by the current legislation, being considered unfit for human consumption. Part of this high microbiological contamination of drinking rainwater could be related to the lack of sanitary education and of an adequate sewerage sanitation system.

Decision-making process in radiology: the magnetic resonance example in the TA context

Based on the report for “Project IV” unit of the PhD programme on Technology Assessment (Doctoral Conference) at Universidade Nova de Lisboa (December 2011). This thesis research has the supervision of António Moniz (FCT-UNL and ITAS-KIT) and Michael Decker (Karlsruhe Institute of Technology-ITAS). Other members of the thesis committee are Carlos Alberto da Silva (University of Évora), José Maria de Albuquerque (Institute of Welding and Quality), Lotte Steuten (University of Twente), Mário Forjaz Secca (FCT-UNL) and Nelson Chibeles Martins (FCT-UNL).

21st century quality: Looking into the “Crystal ball”

The discussion of possible scenarios for the future of Quality is on the priority list of major Quality Practitioners Societies. EOQ – European Organization for Quality (EOQ, 2014) main team for its 58th EOQ-Congress held June 2014 in Göteborg was “Managing Challenges in Quality Leadership” and ASQ - American Society for Quality (ASQ, 2015) appointed “the Future of Quality” for Quality Progress Magazine November 2015 issue. In addition, the ISO 9001:2008 revision process carried by ISO/TC 176 aims to assure that ISO 9001:2015 International Standard remains stable for the next 10 years (ISO, 2014) contributing to an increased discussion on the future of quality. The purpose of this research is to review available Quality Management approaches and outline, adding an academic perspective, expected developments for Quality within the 21st Century. This paper follows a qualitative approach, although data from international organizations is used. A literature review has been undertaken on quality management past and potential future trends. Based on these findings a model is proposed for organization quality management development and propositions for the future of quality management are advanced. Firstly, a state of the art of existing Quality Management approaches is presented, for example, like Total Quality Management (TQM) and Quality Gurus, ISO 9000 International Standards Series (with an outline of the expected changes for ISO 9001:2015), Six Sigma and Business Excellence Models.Secondly, building on theoretical and managerial approaches, a two dimensional matrix – Quality Engineering (QE - technical aspects of quality) and Quality Management (QM: soft aspects of quality) - is presented, outlining five proposed characterizations of Quality maturity levels and giving insights for applications and future developments. Literature review highlights that QM and QE may be addressing similar quality issues but their approaches are different in terms of scope breadth and intensity and they ought to complement and reciprocally reinforce one another. The challenges organizations face within the 21st century have stronger uncertainty, complexity, and differentiation. Two main propositions are advanced as relevant for 21st Century Quality: - QM importance for the sustainable success of organizations will increase and they should be aware of the larger ecosystem to be managed for improvement, possibly leading to the emergence of a new Quality paradigm, The Civilizacional Excellence paradigm. - QE should get more attention from QM and the Quality professionals will have to: a) Master and apply in wider contexts and in additional depth the Quality Tools (basic, intermediate and advanced); b) Have the soft skills needed for its success; c) Be results oriented and better understand and demonstrate the relationships between approaches and results These propositions challenge both scholars and practitioners for a sustained and supported discussion on the future of Quality. “All things are ready, if our mind be so.” (Shakespeare, Henry V, circa 1599).

Projeto e desenvolvimento de células robotizadas para soldadura e cladding

A utilização de equipamentos robóticos para o processo de soldadura por arco elétrico teve um forte crescimento nas décadas de 80 e 90, altura em que o custo e fiabilidade da tecnologia passou a permitir a integração de robôs em linhas de produção ou em células de fabrico. Depressa cresceram as exigências de uma produção com qualidade repetitiva e facilmente ajustável, e as restrições ao uso de processos manuais ou de tecnologias com pouca flexibilidade. Desde o início do século XXI que a renovação de uma estação de fabrico de peças soldadas para produção em série, especialmente no setor automóvel, parece forçada à integração de robôs industriais, que assim se tornaram símbolos de produtividade. A KAMAZ encontra-se atualmente a renovar alguns dos seus processos de fabrico, incluindo as áreas de soldadura por arco ou cladding. Esta Dissertação aborda o trabalho elaborado, depois de contratualizada com a ABB Rússia a instalação de novas células de fabrico robotizado nesta empresa. Este projeto tem início com o levantamento das necessidades, a verificação do processo existente, e a procura da solução tecnológica que se adapte a essas condições e cumpra os requisitos acordados. São realizadas modelações e simulações off-line em 3D, usando o software RobotStudio da ABB, que permitiram testar cada solução e analisar a sua adequação e viabilidade. Para maior garantia de se obter a qualidade esperada na fusão e deposição do material por processo com arco elétrico revestido a gás, foram realizados testes reais utilizando equipamento robótico em condições baseadas nos testes feitos no ambiente virtual. Por último, são ajustadas as localizações dos postos de trabalho ao layout existente e é feito o balanceamento do tempo de operação manual com o tempo do processo robotizado. Este projeto de Tese termina com a aceitação do cliente para a solução encontrada e para os resultados dos testes reais de ambos os processos.

Health-Related Quality of Life of Pediatric Intensive Care Survivors

Objetivo: Avaliar a qualidade de vida relacionada à saúde (QVRS)de crianças sobreviventes à alta da terapia intensiva pediátrica. Métodos: Foi realizada uma avaliação prospectiva da QVRS na admissão e após 6 meses em crianças com idade igual ou superior a 6 anos, internadas em três unidades de terapia intensiva pediátricas (UTIPs) terciárias de maio de 2002 a junho de 2004. A QVRS foi avaliada com o questionário Health Utilities Index Mark 3 (HUI3), aplicado a um representante da criança. Resultados: Das 517 admissões elegíveis, 44 crianças faleceram na UTIP (8,5%) e 320 casos foram avaliados na admissão; entre eles, foi possível realizar o seguimento de 252 casos. Não foram encontradas diferenças estatisticamente significativas entre os escores globais do HUI3 antes da admissão e no seguimento [medianas (intervalo interquartil) de 0,86 (0,42-1,00) e 0,83 (0,45-1,00); p = 0,674, respectivamente]. No âmbito individual, 21% das crianças não apresentaram mudanças na QVRS, foi observada melhora em 40% e agravamento em 38% dos casos. Deficiência grave antes da admissão (escore global do HUI3 < 0,70)esteve presente em 36% dos casos, com melhora no seguimento aos 6 meses em 60% deles. Entre aqueles que apresentaram agravamento da QVRS no seguimento, 45% eram vítimas de trauma. Conclusões: Embora a QVRS seja globalmente semelhante nas duas avaliações, foram encontradas várias diferenças no âmbito individual. As crianças com baixa QVRS antes da admissão (deficiência grave) podem se beneficiar da terapia intensiva pediátrica, visto que muitas dessas crianças melhoraram a QVRS, em comparação com seu estado pré-admissão.

Influência dos Ciclos Térmicos na Soldadura do Aço GRAU 91- SA213 T91 / SA 335 P91

A indústria metalomecânica nacional possui uma larga tradição no fabrico de equipamentos de elevada qualidade nas mais diversas vertentes. Seja em moldes, colunas de geradores de energia eólica, torres de telecomunicações, equipamento para a agropecuária, básculas de camiões ou simplesmente em silos, a indústria metalomecânica portuguesa é reconhecida internacionalmente pela sua competitividade e qualidade. Sectores como o da maquinagem, estampagem e soldadura mantêm viva a economia nacional, exportando produtos e serviços de engenharia que são largamente reconhecidos pelas empresas estrangeiras, tanto na Europa como em África e na América. O sector da construção soldada teve sempre uma forte tradição no nosso país, conhecendo um novo impulso com o fabrico de estruturas metálicas para geradores de energia eólica e torres de telecomunicações. Atualmente esta indústria mantém viva a sua atividade devido a um forte ’know-how’ nesta matéria e a uma qualidade invejável. Apesar do forte ‘know-how’ já existente, esta indústria está constantemente a ser solicitada para novos desafios, passando pela necessidade da aplicação de novos materiais os quais trazem sempre requisitos específicos aos processos, necessitando ser estudados com pormenor. Este estudo baseia-se na necessidade de uma empresa industrial portuguesa precisar de realizar equipamentos em construção soldada com base em aço do tipo Cr-Mo, grau 91, cuja soldadura é tradicionalmente bastante complicada. A realização dos adequados tratamentos ao material, quer antes, quer depois da soldadura, são a garantia de que a qualidade final do produto atinge os níveis exigidos pelos clientes. Assim, o presente estudo, com uma forte componente experimental, permitiu determinar com sucesso quais as melhores condições para o ciclo térmico na soldadura que podem ser aplicadas a esta liga, para que os resultados obtidos possam exibir a qualidade desejada.

Production of aluminium based composites reinforced with embedded NiTi by friction stir welding

Dissertação para a obtenção do grau de Mestre em Engenharia Mecânica

Mental Health and Quality of Life in Alcoholic Liver Disease Patients After Liver Transplantation: a Prospective Controlled Study

OBJECTIVE: Alcoholic liver disease (ALD) is one of the most important indications for liver transplantation. Discordant conclusions have been found concerning quality of life and mental health after transplantation in this particular group. The aim of this work was to investigate improvements in mental health and quality of life among transplanted patients for ALD. METHODS: We studied 45 consecutive transplant candidates with ALD, attending the outpatient clinics. Among these patients we transplanted 24 with the control candidates remaining in wait for transplantation. RESULTS: There was a significant improvement in all mental health and quality of life dimensions among the transplanted ALD group. We also observed a favorable evolution of coping mechanisms (CM) in this group. CONCLUSION: There is a favorable adjustment of ALD patients after transplantation as shown in CM evolution, which might explain the improved mental health and quality-of-life dimensions.

When Does Quality of Life Improve After Liver Transplantation? A Longitudinal Prospective Study

OBJECTIVES: We sought to investigate the improvement in quality of life (mental and physical components) at 1 and 6 months after liver transplantation. METHODS: A sample of liver transplant candidates (n = 60), comprising consecutive patients attending outpatient clinics of a liver transplantation central unit (25% of the patients had familial amyloid polyneuropathy [FAP] and the remaining patents had chronic liver diseases), was assessed by means of the Short Form (SF)-36, Portuguese-validated version, a self-rating questionnaire developed by the Medical Outcome Trust, to investigate certain primary aspects of quality of life, at 3 times: before, and at 1 and 6 months after transplantation. RESULTS: We observed a significant improvement in quality of life (both mental and physical components) by 1 month after transplantation. Between the first month and the sixth month after transplantation, there also was an improvement in the quality of life (both mental and physical components), although only the physical components of quality of life was significantly improved. CONCLUSIONS: Our findings suggested that quality of life improved early after liver transplantation (1 month). Between the first and the sixth months, there only was a significant improvement in the physical quality of life.

Psychosocial Determinants of Quality of Life 6 Months After Transplantation: Longitudinal Prospective Study

OBJECTIVES: We sought to investigate the psychosocial determinants of quality of life at 6 months after transplantation. METHODS: A sample of liver transplant candidates (n = 60), composed of consecutive patients (25% with familial amyloid polyneuropathy [FAP]) attending outpatient clinics was assessed in the pretransplant period using the Neo Five Factor Inventory, Hospital Anxiety and depression Scale (HADS), Brief COPE, and SF-36, a quality-of-life, self-rating questionnaire. Six months after transplantation, these patients were assessed by means of the SF-36. RESULTS: Psychosocial predictors where found by means of multiple regression analysis. The physical component of quality of life at 6 months after transplantation was determined based upon coping strategies and physical quality of life in the pretransplant period (this model explained 32% of variance). The mental component at 6 months after transplantation was determined by depression in the pretransplant period and by clinical diagnoses of patients. Because FAP patients show a lower mental component of quality of life, this diagnosis explained 25% of the variance. CONCLUSIONS: Our findings suggested that coping strategies and depression measured in the pretransplant period are important determinants of quality of life at 6 months after liver transplantation.

Impact of Syncope on Quality of Life: Validation of a Measure in Patients Undergoing Tilt Testing

INTRODUCTION AND OBJECTIVES: Recurrent syncope has a significant impact on quality of life. The development of measurement scales to assess this impact that are easy to use in clinical settings is crucial. The objective of the present study is a preliminary validation of the Impact of Syncope on Quality of Life questionnaire for the Portuguese population. METHODS: The instrument underwent a process of translation, validation, analysis of cultural appropriateness and cognitive debriefing. A population of 39 patients with a history of recurrent syncope (>1 year) who underwent tilt testing, aged 52.1 ± 16.4 years (21-83), 43.5% male, most in active employment (n=18) or retired (n=13), constituted a convenience sample. The resulting Portuguese version is similar to the original, with 12 items in a single aggregate score, and underwent statistical validation, with assessment of reliability, validity and stability over time. RESULTS: With regard to reliability, the internal consistency of the scale is 0.9. Assessment of convergent and discriminant validity showed statistically significant results (p<0.01). Regarding stability over time, a test-retest of this instrument at six months after tilt testing with 22 patients of the sample who had not undergone any clinical intervention found no statistically significant changes in quality of life. CONCLUSIONS: The results indicate that this instrument is of value for assessing quality of life in patients with recurrent syncope in Portugal.

Organizational culture influence on information quality - use of business intelligence systems relationship: portuguese context

Dissertação apresentada como requisito parcial para obtenção do grau de Mestre em Estatística e Gestão de Informação